This application claims priority under 35 U.S.C. xc2xa7119 and/or 365 to German Patent Application Serial No. 100 00 177.7 filed in Germany on Jan. 5, 2000; the entire content of which is hereby incorporated by reference.
The invention relates to a fuse device, in particular for a mortar shell.
Known mortar shells use fuse devices having a spring device which is fitted into the respective fuse device in a mechanically pre-stressed or pre-biased condition. Those known fuse devices are set from the safe position into the armed or live position by means of the pre-biased spring device. The mechanical energy which is stored in the mechanically biased spring device in the safe position adversely influences the safety of the fuse device.
In consideration of those factors, the object of the present invention is to provide such a fuse device in which preferably no mechanical energy (or only a relatively small amount of mechanical energy) is stored in the spring device in the safe position, so that the safety properties in the safe position of the fuse device are substantially improved.
In accordance with the invention, a fuse device for a mortar shell includes a safety element movable from a safety position to an armed position, a spring for producing such movement, and a spring-stressing mechanism for storing energy in the spring to produce the movement. The spring-stressing mechanism comprises an impeller arranged in an air flow path and rotated by an air flow generated in the flow path in response to travel of the mortar shell toward a target. The impeller is operably connected to the spring for stressing the spring in response to being rotated by the air flow.
The fuse device according to the invention has the advantage that no (or very little) mechanical energy tending to arm the device is pre-stored in the spring device in the safe position of the fuse device so that the safety properties are at an optimum. The mechanical biasing of the spring device which is necessary to set the fuse device from the safe position into the armed position is effected only after leaving the barrel from which the mortar shell is launched, by means of the impeller, by virtue of a suitable operative connection of the impeller to the spring device, which spring device can be in the form of a coil torsion spring.